Ok, you lit up my bulb
I had a look to my DNS server log and the only thing "strange" is that is getting blocked some google domains and there is the problem, with mediafire, and with taringa (the other thread on this forum), after took a look to the http dialog with the http monitor (thanks to who ported this add on).
Even what I said in the General forum to Nort (youtube thread), that ajax.googleapis.com is used, basically for ads, looks like sites are using it as a CDN for javascript code. Even the code itself is licensed as GPL by MIT and could be user everywhere else.
In the mediafire case (I didn't dig with taringa, but could be the same), it uses the google host to use this code
https://ajax.googleapis.com/ajax/libs/jquery/1.6/jquery.js that, basically looks like it is used to check visitor environment (browser, PC, mobile) and do whatever needed in each case. In other words, another shit as SWFObject that don't let you to watch flash content if you don't have javascript enabled.
Long story short, another script to trick browsers instead of make a programming nearest standards, even if they lost functionality to show "flashy" websites, hosted on a third party site as a CDN :/
So, guys, don't block ajax.googleapis.com :rollingeyes